(!!!) (Best Pair) 6EM7 GE gray plates NOS 1960's (1.9/45ma and 2.3/44.5ma)
(!!!) (Recommended Pair) 6EM7 Sylvania coin-base branded NOS 1970's (1.8/45ma and 2.0ma/51ma)
(!!) 6EA7=6EM7 Sylvania Zenith coin-base NOS 1970's (1.8/65ma)
6EA7 GE USA black base rebranded Zenith 1960 used/good (3.6ma/35ma)
6EM7 RCA coin-base black plates NOS 1970's broken guide pin (2.4ma/50ma)
6EM7 RCA coin-base black plates used/good 1970's (2.6ma/63ma)
6EM7 RCA coin-base used (2.5ma/28ma)
6EM7 Sylvania coin-base NOS 1970's (1.0ma/42ma)